Panning operations and surround sound decoding operations are mathematically distinct functions that affect the distribution of sound across a speaker system. Panning is the spread of a sound signal into a new multi-channel sound field. Panning is a common function in multi-channel audio systems. Panning functions distribute sound across multi-channel sound systems. In effect, panning “moves” the sound to a different speaker. If the audio is panned to the right, then the right speaker gets most of the audio stream and the left speaker output is reduced.
Surround sound decoding is the mathematical or matrix computations necessary to transform two-channel audio into the necessary multi-channel audio stream to support a surround sound system. Surround sound decoding is the process of transforming two-channel audio input into multi-channel audio output. Audio that is recorded in 5.1 is often encoded in a two-channel format to be broadcast in environments that only support the two-channel format, like broadcast television. Encoding can be of a mathematical form or a matrix form. Mathematical forms require a series of mathematical steps and algorithms to decode. DTS and Dolby Digital perform mathematical encoding. Matrix encoding relies on matrix transforms to encode 5.1 channel audio into a two-channel stream. Audio in matrix encoding can be played either encoded or decoded and be sound acceptable to the end user.